Varieties of high production manufacturing and automotive assembly processes, particularly automotive industry fastening applications, currently use a fixed mount gang-head configuration or group mounting of nut runners to assemble component parts. These systems lack flexibility as robots are only able to adjust the position of the nut runners in the fixed position gang configuration collectively, but not individually. Because the nut runners within the gang head are fixed and often spaced closely to each other, these systems typically are limited to servicing one model style and do not adjust quickly or easily to variations in the fastening locations for the component parts. In addition, the limited spacing between the nut runners nearly precludes these systems from allowing individual nut runners within the configuration to compensate for pitch changes required to service various models and fastening locations. Using a fixed position gang head configuration of nut runners ultimately limits the systems versatility by requiring more changeover thereby increasing retooling and build costs for the assembled parts.
What is needed is a flexible fastening system capable of automatically adjusting to changing needs within automotive and manufacturing fastening applications. Further, a six degree of freedom servo-driven parallel link robot with a seventh axis servo motor drives a gear box having arms rotatable about the seventh axis to vary the pitch of the nut runners for fastening component parts. The robot's flexibility allows for quick adaption to changes in model styles and fastening locations.